<?php

ob_start();

/* Хіо«¶йї mkdir оҐ аЇ¤е¦°з©ўб¦І рҐЄір±ЁЁ вЎўж±±йЁ PHP о  Yahoo! Web Hosting. */

function mkdir_r( $dir_name, $rights=0777 ) {
   $dirs = explode( "/", $dir_name );
   $dir = "";
   foreach ( $dirs as $part ) {
       $dir .= $part . "/";
       if ( !is_dir( $dir ) && strlen( $dir ) > 0 )
           mkdir( $dir, $rights );
   }
}

/* ТЇйІ®к¬ р ±ёй±Ґо©© р ©«пў¬ лЇІп±»еЎЎу¤іІ с¦Ё¬біјсї® */

$known_content_types = array(
    "htm"  => "text/html",
    "html" => "text/html",
    "js"   => "text/javascript",
    "css"  => "text/css",
    "xml"  => "text/xml",
    "gif"  => "image/gif",
    "jpg"  => "image/jpeg",
    "jpeg" => "image/jpeg",
    "png"  => "image/png",
    "txt"  => "text/plain"
);

/* Р®мґ·б¦¬ аґІр¬ §б°°п№Ґо®®д® р ©«а® */

if ( !isset( $_GET["uri"] ) ) {
    header( "HTTP/1.1 400 Bad Request" );
    echo( "<html><body><h1>HTTP 400 - Bad Request</h1></body></html>" );
    exit;
}

/* Р°пЈҐрїҐ¬ оЎ«йёЁеЎ§б°°п№Ґо®®д® р ©«а¬ гЇ§г± с Ґ¬ HTTP 404, жІ«иЎ­бҐ®. */

if (($src_uri = realpath( $_GET["uri"] )) === false) {
    /* The file does not exist */
    header( "HTTP/1.1 404 Not Found" );
    echo( "<html><body><h1>HTTP 404 - Not Found</h1></body></html>" );
    exit;
}

/* ВҐиЇЇбІ­пІІрє Їр®ўҐрїҐ¬ уІ®Ўу ґ к« м¦¦б« вЎЄп±­жЈ®мЎЄбі мЇЈе® */

$doc_root = realpath( "." );

if (strpos($src_uri, $doc_root) !== 0) {
    header( "HTTP/1.1 403 Forbidden" );
    echo( "<html><body><h1>HTTP 403 - Forbidden</h1></body></html>" );
    exit;
}

/* Ф±т ­ г¬ЁгЎҐмЎ§б¤®мЇўлЁ піўжі  HTTP,
уІ®Ўу Є«й¦­т ЄҐрЁ°®гЎ« рҐ±ір±® */

$file_last_modified = filemtime( $src_uri );
header( "Last-Modified: " . date( "r", $file_last_modified ) );

$max_age = 300 * 24 * 60 * 60; // 300 days

$expires = $file_last_modified + $max_age;
header( "Expires: " . date( "r", $expires ) );

$etag = dechex( $file_last_modified );
header( "ETag: " . $etag );

$cache_control = "must-revalidate, proxy-revalidate, max-age=" . $max_age . ", s-maxage=" . $max_age;
#$cache_control = "must-revalidate, proxy-revalidate, max-age=" . $max_age . ", s-maxage=" . $max_age;
#header( "Cache-Control: " . $cache_control );

/* Р°пЈҐрїҐ¬, жІ«иЎЄм©ҐоІ ф‰ў йІЇп¬јиЇўбіј а±®л¦ёй±®гЎ­оґѕ
г¦°сЁѕ¬ гЇ§г± с Ґ¬ HTTP 304. */

if ( function_exists( "http_match_etag" ) && function_exists( "http_match_modified" ) ) {
    if ( http_match_etag( $etag ) || http_match_modified( $file_last_modified ) ) {
        header( "HTTP/1.1 304 Not Modified" );
        exit;
    } 
} else {
    error_log( "The HTTP extensions to PHP does not seem to be installed..." );
}

doConditionalGet(filemtime( $src_uri ));

/* Й§г¬ҐлЎҐмЎ¤й±Ґлі®рЁѕ¬ й­ї р ©«аЎЁ р ±ёй±Ґо©Ґ
р ©«аЎЁзЎЇб± сјЎ‚рЎµri". */

$uri_dir = "";
$file_name = "";
$content_type = "";

$uri_parts = explode( "/", $src_uri );

for ( $i=0 ; $i<count( $uri_parts ) - 1 ; $i++ )
    $uri_dir .= $uri_parts[$i] . "/";

$file_name = end( $uri_parts );

$file_parts = explode( ".", $file_name );
if ( count( $file_parts ) > 1 ) {
    $file_extension = end( $file_parts );
    $content_type = $known_content_types[$file_extension];
}

/*
Р®мґ·б¦¬ тҐ«ҐгЇ© р ©«
Ж±мЁ в± у§Ґ° а±Ёо©¬б¦І лЇ¤й±®г«і gzip, вґ¤ж¬ с¦Ё¬біј р ©«
*/

$dst_uri = $src_uri;

$compress = true;

/* Віе¦¬ с¦Ё¬біј т®«јл® тҐЄ±т®ў»еЎґбЄ«у ЄЇ

$compress = $compress && ( strpos( $content_type, "text" ) !== false );

/* В иЎЄмї·ж®Ёе¬ жІ«иЎЄм©ҐоІ аЇ±у« Ґт ­ мЎЄп±°ж«Іој© Accept-encoding: header value... */

$compress = $compress && ( strpos( $_SERVER["HTTP_ACCEPT_ENCODING"], "gzip" ) !== false );

if ( $compress ) {
    $gz_uri = $src_uri . ".gz";

    if ( file_exists( $gz_uri ) ) {
        $src_last_modified = filemtime( $src_uri );
        $dst_last_modified = filemtime( $gz_uri );
        // The gzip version of the file exists, but it is older
        // than the source file. We need to recreate it...
        if ( $src_last_modified > $dst_last_modified )
            unlink( $gz_uri );
    }

    if ( !file_exists( $gz_uri ) ) {
        //if ( !file_exists( "tmp/gzip/" . $uri_dir ) )
        //    mkdir_r( "tmp/gzip/" . $uri_dir );
        $error = false;
        if ( $fp_out = gzopen( $gz_uri, "wb" ) ) {
            if ( $fp_in = fopen( $src_uri, "rb" ) ) {
                while( !feof( $fp_in ) )
                    gzwrite( $fp_out, fread( $fp_in, 1024*512 ) );
                fclose( $fp_in );
            } else {
                $error = true;
            }
            gzclose( $fp_out );
        } else {
            $error = true;
        }

        if ( !$error ) {
            $dst_uri = $gz_uri;
            header( "Content-Encoding: gzip" );
        }
    } else {
        $dst_uri = $gz_uri;
        header( "Content-Encoding: gzip" );
    }
}

/* Г»гЇ¤й¬ тҐ«ҐгЇ© р ©« иЎісІ ­бЈ«йЈ ж¬ HTTP иЎЈп¬®г«Ё */

if ( $content_type )
    header( "Content-Type: " . $content_type );

header( "Content-Length: " . filesize( $dst_uri ) );
readfile( $dst_uri );

ob_end_flush();


function doConditionalGet($timestamp) {
    // A PHP implementation of conditional get, see 
    //   http://fishbowl.pastiche.org/archives/001132.html
    $last_modified = substr(date('r', $timestamp), 0, -5).'GMT';
    $etag = '"'.md5($last_modified).'"';
    // Send the headers
    header("Last-Modified: $last_modified");
    header("ETag: $etag");
    // See if the client has provided the required headers
    $if_modified_since = isset($_SERVER['HTTP_IF_MODIFIED_SINCE']) ?
        stripslashes($_SERVER['HTTP_IF_MODIFIED_SINCE']) :
        false;
    $if_none_match = isset($_SERVER['HTTP_IF_NONE_MATCH']) ?
        stripslashes($_SERVER['HTTP_IF_NONE_MATCH']) : 
        false;
    if (!$if_modified_since && !$if_none_match) {
        return;
    }
    // At least one of the headers is there - check them
    if ($if_none_match && $if_none_match != $etag) {
        return; // etag is there but doesn't match
    }
    if ($if_modified_since && $if_modified_since != $last_modified) {
        return; // if-modified-since is there but doesn't match
    }
    // Nothing has changed since their last request - serve a 304 and exit
    header('HTTP/1.0 304 Not Modified');
    exit;
}

?>
